JP2011104693A - Substrate polishing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate polishing device which prevents an abrasive liquid or a cleaning liquid from staying in a side groove for collecting the abrasive liquid or the cleaning liquid falling down from a polishing stage where a substrate to be polished is mounted. <P>SOLUTION: A nozzle 20 for jetting a fluid to the downstream side of the side groove 10 is arranged in the side groove 10 for collecting the abrasive liquid or the cleaning liquid falling down from the polishing stage 3 where the substrate W to be polished is mounted, so that the liquid in the side groove 10 is washed away by the pressure of the fluid jetted from the nozzle 20. When the side groove 10 has no tilt or a tilt is not sufficiently steep if there is the tilt and the abrasive liquid or the cleaning liquid are difficult to flow, the flow of the abrasive liquid or the cleaning liquid in the side groove 10 is smoothed so that it can sufficiently be collected. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a substrate polishing apparatus for polishing a surface of a substrate such as a glass substrate used for a liquid crystal display panel or the like.

  In recent years, liquid crystal display panels have been widely used as display units for home appliances such as computers and televisions. In general, a liquid crystal display panel has a configuration in which a pair of glass substrates, each composed of a thin film transistor (TFT) array substrate and a color filter (CF) substrate, are arranged opposite to each other in parallel at a predetermined interval, and liquid crystal is filled between the substrates. I am doing.

  A plurality of pixel electrodes are formed in a matrix on the TFT array substrate, and a common electrode is formed on almost the entire surface of the CF substrate, and the orientation of the liquid crystal can be controlled by changing the voltage applied between these electrodes. Can be done.

  In the manufacturing process of such a liquid crystal display panel, those that do not satisfy the predetermined quality standards required for the TFT array substrate and the CF substrate cannot be used for the liquid crystal display panel and are discarded.

  Therefore, various thin films formed on the glass substrate are removed from the discarded materials and regenerated and reused as a glass substrate for a TFT array substrate or a CF substrate.

  As a method of removing the film formed on the surface of such a glass substrate, there is a method of removing by polishing. Conventionally, a substrate polishing apparatus 50 as shown in FIG. 9 is used as an apparatus for polishing the surface of such a glass substrate. In this case, FIG. 9 shows a side view of the main part of the substrate polishing apparatus 50, and FIG. 10 shows a top view thereof.

  As shown in the figure, the substrate polishing apparatus 50 includes polishing surface plates 51 and 51 and a polishing stage 52 that are arranged to face each other in the vertical direction. A polishing cloth 54 is attached to the lower surface of the polishing surface plate 51 having a circular shape via a double-sided adhesive sheet, and the abrasive liquid supplied from the upper surface of the polishing surface plate 51 by the abrasive liquid supply nozzle 55 is The inside of the polishing surface plate 51 flows down and is supplied to the polishing pad 54.

  The polishing stage 52 is a member made of porous ceramic having a rectangular shape substantially the same size as the glass substrate W, and the polishing stage is evacuated by a vacuum pump (not shown) connected to the lower portion of the polishing stage 52. The glass substrate W placed on 52 can be sucked and held on its upper surface.

  Then, the polishing surface plate 51 is pressed against the polishing stage 52, the glass substrate W is sandwiched between the polishing cloth 54 and the polishing stage 52 of the polishing surface plate 51, and the polishing liquid is supplied to the polishing cloth 54 while polishing. The glass substrate W is polished by repeatedly moving (swinging) the polishing surface plate 51 in the direction indicated by the arrow E while rotating the surface plate 51 and the polishing stage 52.

  As the polishing abrasive liquid supplied to the polishing surface plate 51, a suspension (slurry) in which abrasive grains (abrasive material) made of powdered alumina, cerium oxide or the like is dispersed in, for example, an alkaline solution or water is used. It has been. In this case, the abrasive liquid is supplied from the abrasive liquid storage tank 57 to the polishing surface plate 51 via the abrasive liquid supply nozzle 55 by the abrasive liquid supply pump 58.

  After such a polishing process of the glass substrate W, a cleaning process of the polishing surface plate 51 and the polishing stage 52 is performed. In this case, a cleaning liquid such as pure water supplied from the upper surface of the polishing surface plate 51 by the cleaning liquid supply nozzle 59 flows down the polishing surface plate 51 and is supplied to the polishing cloth 54. 54 and the upper surface of the polishing stage 52 are cleaned by this cleaning liquid.

  As shown in the figure, side grooves 60, 60 are provided on both the left and right sides below the polishing stage 52, and the abrasive and cleaning liquid flowing down from the polishing stage 52 are collected by the side grooves 60, 60 and then out of the apparatus. It is supposed to be discharged.

  Normally, the abrasive liquid flowing down from the polishing stage 52 in the polishing process flows through the side groove 60 and returns to the abrasive liquid storage tank 57 again via the recovery tank 62. Further, in the first half of the cleaning process, the cleaning liquid flowing in the side groove 60 contains a lot of abrasive liquid. Therefore, this is a kind of solid-liquid separation device that collects this in the intermediate tank 63 and uses centrifugal force. The high-concentration abrasive liquid is separated and removed by the cyclone 64 and reused.

  Further, in the latter half of the cleaning process, only the cleaning liquid flows in the side groove 60, so that the cleaning liquid recovered from the side groove 60 is sent to the drain pit 66 via the drain tank 65. In this case, reference numeral 61 is a switching valve that can switch the destination of the liquid discharged from the side groove 60 to the recovery tank 62, the intermediate tank 63, and the drain tank 65. In addition, the following patent document is mentioned as a prior art document relevant to this invention.

JP 2005-40916 A

  However, the side groove 60 provided below the polishing stage 52 is not inclined at all, or even if there is an inclination, the inclination is not sufficiently steep and the abrasive or cleaning liquid may not flow easily. There was a problem that the flow of the liquid inside was poor and the abrasive liquid and cleaning liquid could not be sufficiently recovered.

  Therefore, the problem to be solved by the present invention is to prevent these liquids from staying in the side groove for collecting the abrasive liquid or the cleaning liquid flowing down from the polishing stage on which the substrate to be polished is placed. A substrate polishing apparatus is provided.

  In order to solve the above-mentioned problems, a substrate polishing apparatus according to the present invention supplies a fluid toward a downstream side of a side groove in a side groove for collecting an abrasive liquid or a cleaning liquid flowing down from a polishing stage on which a substrate to be polished is placed. The gist is that a nozzle to be ejected is provided.

  According to the substrate polishing apparatus having such a configuration, the nozzle for ejecting fluid toward the downstream side of the side groove is provided in the side groove for collecting the polishing liquid or the cleaning liquid. It can be swept away by the pressure of the fluid ejected from. As a result, even if there is no inclination in the side groove, or there is an inclination, the inclination is not sufficiently steep and it is difficult for the abrasive liquid or cleaning liquid to flow. These can be recovered sufficiently.

  In this case, if a plurality of the nozzles are provided from the upstream side to the downstream side of the side groove, the flow of the liquid in the side groove is made smooth from the upstream side to the downstream side so that the liquid stays (residual) in the side groove. ) Can be recovered. Further, if the plurality of nozzles are provided at the tips of the plurality of branch portions branched from the one fluid supply hose disposed in the side groove, the plurality of nozzles can be easily placed in the side groove. It can be arranged. Furthermore, if a plurality of fluid ejection holes are formed at the tip of the nozzle along the width direction of the side groove, the liquid flow in the side groove can be made smoother.

  When the polishing liquid flows down from the polishing stage into the side groove, the concentration of the polishing liquid used for substrate polishing is reduced if the fluid ejected from the nozzle is air or the polishing liquid. It can be recovered and reused without any problems.

  Further, when the cleaning liquid flows down from the polishing stage into the side groove, if the fluid ejected from the nozzle is air, the cleaning liquid in the side groove can easily flow to the drain tank 65 described above. Can be recovered and drained. When the flow of the cleaning liquid in the side groove is bad, that is, when the next substrate polishing process is started while all of the cleaning liquid used in the cleaning process remains in the side groove without being collected in the drain tank 65, from the inside of the side groove. The remaining cleaning liquid is mixed with the polishing liquid recovered in the recovery tank 62 and sent to the polishing liquid storage tank 57 again, and the concentration of the polishing liquid in the polishing liquid storage tank 57 is reduced. However, since the cleaning liquid can be collected by the air ejected from the nozzle so that the cleaning liquid does not remain in the side groove, the occurrence of such a problem is prevented.

  Further, if a plurality of air ejection holes for air bubbling into the liquid in the side groove are formed at the bottom of the side groove, the liquid in the portion such as the end in the side groove where the liquid is liable to stay. It is possible to make the flow of air smooth by air bubbling. In this case, if the air ejection hole is formed so as to be inclined obliquely upward toward the downstream side, the flow of the liquid in the side groove can be made more effective and smooth.

  According to the substrate polishing apparatus of the present invention, the nozzle for ejecting the fluid toward the downstream side of the side groove is provided in the side groove for collecting the polishing liquid or the cleaning liquid, so that the liquid in the side groove can easily flow. be able to. As a result, even if there is no inclination in the side groove, or there is an inclination, the inclination is not sufficiently steep and it is difficult for the abrasive liquid or cleaning liquid to flow, so that the abrasive liquid or cleaning liquid can be sufficiently recovered.

1 is a side view schematically showing a substrate polishing apparatus according to a first embodiment of the present invention. FIG. 2 is a top view of the substrate polishing apparatus of FIG. 1. FIG. 2 is an external perspective view of a side groove and a fluid ejection nozzle included in the substrate polishing apparatus of FIG. 1. It is the side view which showed typically the substrate polishing apparatus which concerns on the 2nd Embodiment of this invention. FIG. 5A is an external perspective view of a side groove and a fluid ejection nozzle included in the substrate polishing apparatus of FIG. 4, and FIG. 5B is a cross-sectional view of the side groove of FIG. It is the top view which showed typically the substrate polishing apparatus which concerns on the 3rd Embodiment of this invention. It is an external appearance perspective view of the fluid supply hose provided with the fluid ejection nozzle applied as a modification of the 1st-3rd embodiment of this invention. It is the top view which showed typically the state by which the fluid supply hose of FIG. 7 was arrange | positioned in the side groove | channel of a substrate polishing apparatus. It is the side view which showed typically the substrate polishing apparatus used conventionally. FIG. 10 is a top view of the substrate polishing apparatus of FIG. 9.

  Embodiments of a substrate polishing apparatus according to the present invention will be described below in detail with reference to the drawings. First, a first embodiment of a substrate polishing apparatus according to the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 and 2, the substrate polishing apparatus 1 includes polishing surface plates 2 and 2 and a polishing stage 3 that are arranged to face each other in the vertical direction.

  A polishing cloth 4 is attached to the lower surface of the polishing surface plate 2 having a circular shape via a double-sided adhesive sheet. The polishing cloth 4 is made of foamed urethane, non-woven fabric or the like that does not contain abrasive grains therein, and its lower surface is a polishing surface for polishing the upper surface of the glass substrate W. The polishing surface plate 2 is connected to a motor (not shown) and a lifting cylinder, which are disposed above it, via a rotatable support shaft 2a, and can move up and down as shown by arrows A and B in the drawing. It can rotate around the axis 2a. Further, the polishing surface plate 2 can be repeatedly moved (swinged) as shown by an arrow D in FIG. 2 by a swinging arm (not shown).

  An abrasive liquid supply nozzle 5 is disposed above the polishing surface plate 2, and abrasive grains (abrasive material) made of powdered alumina, cerium oxide, or the like are dispersed in water from the abrasive liquid supply nozzle 5. A polishing liquid comprising a suspension (slurry) is supplied to the polishing surface plate 2. The supplied abrasive liquid flows down the polishing surface plate 2 and is supplied to the polishing pad 4.

  In this case, the abrasive liquid is stored in the abrasive liquid storage tank 7, and the abrasive liquid in the abrasive liquid storage tank 7 is pumped up by the abrasive liquid supply pump 8 provided in the abrasive liquid storage tank 7 to supply the abrasive liquid. It is supplied to the polishing surface plate 2 through the nozzle 5.

  A cleaning liquid supply nozzle 9 is disposed above the polishing surface plate 2, and a cleaning liquid such as pure water is supplied from the cleaning liquid supply nozzle 9 to the polishing surface plate 2. The supplied cleaning liquid flows down the polishing surface plate 2 and is supplied to the polishing pad 4.

  The polishing stage 3 is a member made of porous ceramic having a rectangular shape that is almost the same size as the glass substrate W. The polishing stage 3 is evacuated by a vacuum pump (not shown) connected to the lower portion of the polishing stage 3. The placed glass substrate W can be sucked and held on its upper surface.

  The polishing stage 3 is connected to a motor (not shown) disposed below the stage shaft 3a, and the polishing stage 3 is rotatable around the stage axis 3a as indicated by an arrow C in the drawing. It has become.

  As shown in the drawing, side grooves 10 and 10 as bottom portions of a frame 6 surrounding the polishing stage 3 are provided on both the left and right sides below the polishing stage 3, so that the abrasive liquid and the cleaning liquid flowing down from the polishing stage 3 can flow. It is collected by the side grooves 10 and 10 and discharged out of the apparatus.

  In such a polishing process of the glass substrate W with the abrasive liquid of the substrate polishing apparatus 1, the abrasive liquid flowing down from the polishing stage 3 flows through the side groove 10 and returns to the abrasive liquid storage tank 7 again via the recovery tank 12. It is like that. That is, the abrasive liquid flowing down from the polishing stage 3 after being used for polishing the glass substrate W flows through the side groove 10 and returns to the abrasive liquid storage tank 7 again via the recovery tank 12, and the abrasive liquid storage tank 7. It is designed to be mixed with the abrasive fluid stored inside.

  Further, in the cleaning process of the polishing surface plate 2 and the polishing stage 3 using the cleaning liquid of the substrate polishing apparatus 1, in the first half of the cleaning process, the cleaning liquid flowing down from the polishing stage 3 and flowing in the side groove 10 is used as an abrasive liquid. Since many of these are mixed, the intermediate tank 13 collects them. The liquid in which the cleaning liquid and the abrasive liquid collected in the intermediate tank 13 are mixed is sent to a cyclone 14 which is a kind of solid-liquid separation device using centrifugal force, and the high-concentration abrasive liquid is separated and taken out by the cyclone 14. In other words, the abrasive grains taken out can be reused.

  Further, in the latter half of the cleaning process, since the abrasive liquid is hardly mixed in the cleaning liquid flowing down from the polishing stage 3 and flowing in the side groove 10, almost only the cleaning liquid flows in the side groove 10. The cleaned cleaning liquid is sent to the drain pit 16 via the drain tank 15. Reference numeral 11 denotes a switching valve that can switch the destination of the liquid discharged from the downstream end of the side groove 10 to each of the recovery tank 12, the intermediate tank 13, and the drainage tank 15.

  A plurality of fluid ejection nozzles 20 are arranged in the side groove 10 for collecting the polishing liquid and the cleaning liquid flowing down from the polishing stage 3. In this case, three fluid ejection nozzles 20 are respectively disposed at three locations upstream, midstream, and downstream of the side groove 10. The fluid ejection nozzle 20 is connected to the tip of a branch portion 21a that branches from a single fluid supply hose 21 having flexibility. The fluid supply hose 21 is connected to a compressed air supply source 23 via an on-off valve 22 that can be closed and opened.

  As shown in FIG. 3, a plurality of fluid ejection holes 20a arranged in the width direction of the side groove 10 are formed at the tip of the fluid ejection nozzle 20, and air is ejected from each of these fluid ejection holes 20a. It has become so. In this case, the fluid ejection hole 20 a of the fluid ejection nozzle 20 is directed to the downstream side of the side groove 10, and air is ejected from the upstream side to the downstream side of the side groove 10. Thereby, the abrasive liquid and the cleaning liquid in the side groove 10 can be pushed away toward the downstream side by the pressure of the air ejected from the fluid ejection nozzle 20.

  In the polishing step of the substrate polishing apparatus 1 having such a configuration, first, the glass substrate W is placed on the upper surface of the polishing stage 3 by a substrate transfer means (not shown). The glass substrate W placed on the polishing stage 3 is sucked and held on the polishing stage 3 by suction with a vacuum pump (not shown).

  Next, the upper surface of the glass substrate W is pressed with a predetermined pressure by driving the polishing surface plate 2 by a lifting cylinder (not shown). Next, the abrasive liquid supply pump 8 is driven to pump up the abrasive liquid stored in the abrasive liquid storage tank 7, and the abrasive liquid is sent out to the abrasive liquid supply nozzle 5. The abrasive liquid discharged from the abrasive liquid supply nozzle 5 is supplied to the polishing cloth 4 of the polishing surface plate 2.

  Then, while supplying the polishing liquid to the polishing cloth 4 and rotating the polishing surface plate 2 and the polishing stage 3, the polishing surface plate 2 is repeatedly moved (oscillated) as indicated by the arrow D to thereby rotate the glass substrate W. Is polished. In this case, the switching valve 11 is switched so that the delivery destination of the liquid discharged from the side groove 10 is the collection tank 12.

  While the glass substrate W is being polished, the on-off valve 22 is opened and air is ejected from the fluid ejection nozzle 20 via the fluid supply hose 21. When air is ejected from the fluid ejection nozzle 20 disposed in the side groove 10 in this way, the abrasive fluid in the side groove 10 that has flowed down from the polishing stage 3 and received by the side groove 10 is downstream due to the pressure of the air. It is swept away to the side. As a result, the abrasive liquid in the side groove 10 flows smoothly from the upstream side to the downstream side of the side groove 10 without stagnation.

  When the flow of the abrasive liquid in the side groove 10 is weak, a part of the abrasive grains contained in the abrasive liquid is precipitated in the side groove 10, and as a result, the concentration of the recovered abrasive liquid is lowered. When the abrasive liquid having such a reduced concentration is returned to the abrasive liquid storage tank 7 again via the recovery tank 12 and mixed with the abrasive liquid in the abrasive liquid storage tank 7, the concentration of the abrasive liquid decreases. End up.

  Usually, the concentration of the abrasive liquid stored in the abrasive liquid storage tank 7, that is, the content of abrasive grains in the abrasive liquid is set to 10 weight percent, for example, and when the concentration of this abrasive liquid decreases, The processing accuracy of polishing the glass substrate W becomes unstable.

  Therefore, a fluid ejection nozzle 20 is disposed in the side groove 10, air is ejected from the fluid ejection nozzle 20 toward the downstream side, and the abrasive liquid in the side groove 10 is pushed away by the pressure of the air to flow the abrasive liquid. By making this good, it is suppressed that a part of the abrasive grains contained in the abrasive liquid is precipitated in the side groove 10. Accordingly, the concentration of the abrasive liquid recovered from the side groove 10 can be returned to the abrasive liquid storage tank 7 without lowering the concentration, and the concentration of the abrasive liquid in the abrasive liquid storage tank 7 can be stabilized. It becomes possible. In this case, since the fluid ejected from the fluid ejection nozzle 20 is air, there is no influence on the concentration of the recovered abrasive liquid. Further, even in the case of a side groove having no inclination or a side groove that cannot be modified to increase the inclination, the fluid flow in the side groove can be made smooth simply by disposing the fluid ejection nozzle 20 in the side groove. be able to.

  As described above, when the concentration of the abrasive liquid in the abrasive liquid storage tank 7 is stabilized, the processing accuracy of polishing the glass substrate W is stabilized. In addition, the number of times of replenishing abrasive grains in the abrasive liquid storage tank 7 can be reduced, so that the cost can be reduced by reducing the amount of abrasive grains used. Furthermore, since the amount of abrasive grains used is reduced, the cost for discarding abrasive grains can be reduced, and the burden on the environment is reduced. And since the accumulation amount (precipitation amount) of the abrasive grains in the side groove 10 is reduced, cleaning in the substrate polishing apparatus 1 is facilitated, and the burden on the operator is reduced.

  When the polishing process of the glass substrate W with such an abrasive liquid is completed, the supply of the abrasive liquid is stopped and the polishing surface plate 2 and the polishing stage 3 are cleaned with the cleaning liquid. The cleaning liquid discharged from the cleaning liquid supply nozzle 9 is supplied to a brush (not shown), and the polishing cloth 4 of the polishing surface plate 2 is cleaned by this brush. The polishing stage 3 is cleaned by a cleaning liquid supplied from a loader (not shown) that carries the glass substrate W into the substrate polishing apparatus 1 or a shower nozzle attached to an unloader (not shown) that carries the glass substrate W out of the substrate polishing apparatus 1. To be done. In this case, the destination of the liquid discharged from the side groove 10 by the switching valve 11 is switched to the intermediate tank 13 in the first half of the cleaning process. Further, in the latter half of the cleaning process, the destination of the liquid discharged from the side groove 10 is switched to the drain tank 15 by the switching valve 11.

  In the cleaning process of the polishing surface plate 2 and the polishing stage 3 with such a cleaning liquid, in the first half of the cleaning process, a large amount of abrasive liquid is mixed in the cleaning liquid flowing down from the polishing stage 3 and flowing in the side grooves 10. Then, this is recovered in the intermediate tank 13 and the high-concentration abrasive liquid is separated and taken out by the cyclone 14.

  Even during such a cleaning process, the on-off valve 22 is opened, and air is ejected from the fluid ejection nozzle 20 via the fluid supply hose 21. Thus, when air is ejected from the fluid ejection nozzle 20 disposed in the side groove 10, the cleaning liquid and the abrasive liquid in the side groove 10 that flows down from the polishing stage 3 and is received by the side groove 10 due to the pressure of the air. The mixed liquid is pushed away to the downstream side.

  Thereby, the liquid in which the cleaning liquid and the abrasive liquid in the side groove 10 are mixed flows smoothly from the upstream side to the downstream side of the side groove 10 without staying. In this case, the mixed liquid of the cleaning liquid and the polishing liquid discharged from the side groove 10 is sent to the cyclone 14 through the intermediate tank 13, but the polishing liquid remaining in the polishing process can be sufficiently recovered. The amount of abrasive grains taken out by the cyclone 14 can be increased as compared with the prior art. As a result, the amount of abrasive grains reused as abrasive grains to be filled in the abrasive liquid supply tank 7 can be increased, so that the cost for the material costs of the abrasive grains can be reduced.

  Next, in the latter half of the cleaning process, since the abrasive liquid is hardly mixed in the cleaning liquid flowing down from the polishing stage 3 and flowing in the side groove 10, only the cleaning liquid flows in the side groove 10, so that it is discharged from the side groove 10. The cleaned cleaning liquid is sent to the drain pit 16 via the drain tank 15. In this case, the destination of the liquid discharged from the side groove 10 is switched to the drain tank 15 by the switching valve 11.

  When such a cleaning process is completed, the supply of the cleaning liquid is stopped and the polishing process to the next glass substrate W is started. If the cleaning liquid remains in the side groove 10, the next glass The abrasive liquid that is used for polishing the substrate W and flows down from the polishing stage 3 is mixed with the remaining cleaning liquid, and the concentration of the abrasive liquid decreases. When the abrasive liquid having such a reduced concentration is returned to the abrasive liquid storage tank 7 again via the recovery tank 12 and mixed with the abrasive liquid in the abrasive liquid storage tank 7, the concentration of the abrasive liquid decreases. End up.

  Therefore, in this case as well, the air is ejected from the fluid ejection nozzle 20 disposed in the side groove 10 toward the downstream side, and the cleaning liquid in the side groove 10 is pushed away by the pressure of the air to improve the flow. The cleaning liquid can be discharged without remaining in the side groove 10. Thereby, in the polishing process of the next glass substrate W, it can be returned to the abrasive liquid storage tank 7 without reducing the concentration of the abrasive liquid recovered from the side groove 10, and the abrasive in the abrasive liquid storage tank 7 can be restored. It becomes possible to stabilize the concentration of the liquid.

  Next, a second embodiment of the substrate polishing apparatus according to the present invention will be described with reference to FIGS. In addition, about the same structure as 1st Embodiment mentioned above, the same code | symbol is attached | subjected and description is abbreviate | omitted and it demonstrates centering on a different point.

  As shown in FIGS. 4 and 5A, a plurality of air ejection holes 10b are formed in the bottom portion 10a of the side groove 10 provided in the substrate polishing apparatus 30 from the upstream side to the downstream side. The air ejection hole 10b is connected to the compressed air supply source 23 via the on-off valve 31 so that air can be ejected. In this case, when the abrasive liquid or the cleaning liquid flows in the side groove 10, air is bubbled into the liquid by ejecting air from the air ejection hole 10b.

  In particular, when the abrasive fluid flows in the side groove 10, air bubbling is performed to suppress the precipitation of abrasive grains in the abrasive fluid on the bottom portion 10a. In addition, since the abrasive particles settled in the portion of the side groove 10 where the liquid flow is weak, such as a corner portion, can be suspended by such air bubbling, the grinding by the pressure of the air ejected from the fluid ejection nozzle 20 is possible. Due to the synergistic effect with the pushing of the liquid, it is possible to efficiently flow the abrasive liquid to the downstream side. In this case, as shown in FIG. 5B, if the air ejection hole 10b is formed in a shape inclined obliquely upward toward the downstream side, together with the action and effect of floating abrasive grains precipitated by air bubbling, It is possible to achieve the action and effect of pushing the abrasive liquid in the side groove 10 to the downstream side.

  Next, a third embodiment of the substrate polishing apparatus according to the present invention will be described with reference to FIG. In addition, about the same structure as 1st Embodiment mentioned above, the same code | symbol is attached | subjected and description is abbreviate | omitted and it demonstrates centering on a different point.

  In the substrate polishing apparatus 40 as shown in the figure, the fluid supply hose 21 is connected to the abrasive liquid supply pump 8 and the compressed air supply source 23 via the switching valve 41, and air or abrasive liquid is supplied from the fluid ejection nozzle 20. It is possible to erupt.

  In such a substrate polishing apparatus 40, while the glass substrate W is being polished, the fluid supply hose 21 is connected to the abrasive liquid supply pump 8 by the operation of the switching valve 22, and the fluid supply hose 21 is interposed. Thus, the abrasive liquid is ejected from the fluid ejection nozzle 20. When the abrasive liquid is ejected from the fluid ejection nozzle 20 disposed in the side groove 10 in this manner, the pressure in the side groove 10 that flows down from the polishing stage 3 and is received by the side groove 10 due to the pressure of the ejected abrasive liquid. The abrasive liquid is forced to flow downstream. As a result, the abrasive liquid in the side groove 10 flows smoothly from the upstream side to the downstream side of the side groove 10 without stagnation.

  Since the fluid ejected from the fluid ejection nozzle 20 is the same as the abrasive liquid supplied from the abrasive liquid supply pump 8, that is, the abrasive liquid used for polishing, the concentration of the abrasive liquid recovered in the side groove 10. There is no impact on

  Therefore, as in the case of the first embodiment described above, the abrasive liquid recovered from the side groove 10 can be returned to the abrasive liquid storage tank 7 without lowering the concentration, and the abrasive liquid storage tank 7 can be restored. It is possible to stabilize the concentration of the abrasive liquid. Further, the timing for supplying or stopping the supply of the abrasive liquid to the polishing surface plate 2 and the timing for supplying or stopping the supply of the abrasive liquid to the fluid ejection nozzle 20 can be made coincident with each other. Without adding one, it is possible to supply the abrasive liquid to both the polishing surface plate 2 and the fluid ejection nozzle 20 only by distributing the piping from one abrasive liquid supply pump 8 as shown in the figure.

  When the polishing process is completed and the cleaning process is started, the fluid supply hose 21 is connected to the compressed air supply source 23 by the operation of the switching valve 41, and the air is discharged from the fluid ejection nozzle 20 through the fluid supply hose 21. In the first half and the second half of the cleaning process similar to the first embodiment described above, the cleaning liquid in the side groove 10 is pushed away by air.

  According to the substrate polishing apparatus according to the present invention described above, the nozzle 20 for ejecting fluid toward the downstream side of the side groove 10 is provided in the side groove 10 for collecting the polishing liquid or the cleaning liquid. The liquid inside can be swept away by the pressure of the fluid ejected from the nozzle 20. Thereby, even if there is no inclination in the side groove 10 or there is an inclination, the inclination is not sufficiently steep and it is difficult for the abrasive liquid or cleaning liquid to flow, and the flow of the abrasive liquid or cleaning liquid in the side groove 10 is made smooth. These can be recovered sufficiently.

  In this case, since a plurality of nozzles 20 are provided from the upstream side to the downstream side of the side groove 10, the flow of the liquid in the side groove 10 is made smooth from the upstream side to the downstream side, and liquid does not stay (residual) in the side groove. Can be recovered. In addition, since the plurality of nozzles 20 are provided at the tips of the plurality of branch portions 21a branched from one fluid supply hose 21 disposed in the side groove 10, the plurality of nozzles 20 can be easily placed in the side groove 10. Can be arranged. Furthermore, since a plurality of fluid ejection holes 20a along the width direction of the side groove 10 are formed at the tip of the nozzle 20, the flow of the liquid in the side groove 10 can be made smoother.

  Further, when the abrasive liquid flows down from the polishing stage 3 into the side groove 10, if the fluid ejected from the nozzle 20 is air or abrasive liquid, the concentration of the abrasive liquid used for substrate polishing is reduced. It can be recovered and reused without any problems.

  When the cleaning liquid flows down from the polishing stage into the side groove 10, if the fluid ejected from the nozzle 20 is air, the cleaning liquid in the side groove 10 can easily flow and can be easily recovered. When the flow of the cleaning liquid in the side groove 10 is poor, that is, when the next glass substrate W polishing process is started while all the cleaning liquid used in the cleaning process is not collected and remains in the side groove 10, The remaining cleaning liquid is mixed with the abrasive liquid that is collected and sent to the abrasive liquid storage tank 7 again. This causes a problem that the concentration of the abrasive liquid in the abrasive liquid storage tank 7 is reduced. Since the cleaning air can be recovered so that the cleaning liquid does not remain in the side groove 10, the occurrence of such a problem is prevented.

  Further, if a plurality of air ejection holes 10b for bubbling air into the liquid in the side groove 10 are formed in the bottom 10a of the side groove 10, the corners in the side groove 10 where the liquid easily accumulates, etc. It is possible to smooth the flow of the liquid in this part by air bubbling. In this case, if the air ejection hole 10b is formed so as to be inclined obliquely upward toward the downstream side, the flow of the liquid in the side groove 10 can be made more effective and smooth.

  Although the embodiments of the substrate polishing apparatus according to the present invention have been described above, the present invention is not limited to these embodiments, and can be implemented in various modes without departing from the gist of the present invention. Of course.

  For example, the fluid supply hose 26 shown in FIG. 7 includes a fluid ejection nozzle 25 having a fluid ejection hole 25a formed in the tube wall so as to be inclined from the inside toward the downstream side, from the upstream side to the downstream side. A plurality of nozzles are provided, and air or abrasive liquid is jetted obliquely from the fluid jet nozzle 25 toward the downstream side. Therefore, as shown in FIG. 8, even if the fluid supply hose 26 having such a configuration is arranged in the side groove 10, the liquid in the side groove 10 is pushed away by the pressure of the fluid ejected from the fluid ejection nozzle 25. However, the present invention is not limited to the above-described embodiment.

1, 30, 40 Substrate polishing apparatus 2 Polishing surface plate 3 Polishing stage 4 Polishing cloth 5 Abrasive liquid supply nozzle 6 Frame body 7 Abrasive liquid storage tank 8 Abrasive liquid supply pump 9 Cleaning liquid supply nozzle 10 Side groove 11 Switching valve 12 Recovery tank 13 Intermediate Tank 14 Cyclone 15 Drain tank 16 Drain pit 20 Fluid ejection nozzle 20a Fluid ejection hole 21 Fluid supply hose 21a Branch 22 On-off valve 23 Compressed air supply source 25 Fluid ejection nozzle 25a Fluid ejection hole 26 Fluid supply hose 31 On-off valve 41 Switching valve W glass substrate

Claims (9)

  Substrate polishing characterized in that a nozzle that ejects fluid toward the downstream side of the side groove is provided in a side groove that collects polishing liquid or cleaning liquid flowing down from a polishing stage on which a substrate to be polished is placed apparatus.   The substrate polishing apparatus according to claim 1, wherein a plurality of the nozzles are provided from the upstream side to the downstream side of the side groove.   3. The substrate polishing apparatus according to claim 1, wherein the plurality of nozzles are provided at tips of a plurality of branch portions branched from one fluid supply hose disposed in the side groove. 4. .   4. The substrate polishing apparatus according to claim 1, wherein a plurality of fluid ejection holes along the width direction of the side groove are formed at the tip of the nozzle. 5.   5. The substrate polishing apparatus according to claim 1, wherein when a polishing liquid flows down from the polishing stage into the side groove, the fluid ejected from the nozzle is air. 6.   5. The substrate polishing apparatus according to claim 1, wherein when the abrasive liquid flows from the polishing stage into the side groove, the fluid ejected from the nozzle is an abrasive liquid. 6.   5. The substrate polishing apparatus according to claim 1, wherein when a cleaning liquid flows from the polishing stage into the side groove, the fluid ejected from the nozzle is air. 6.   The substrate polishing apparatus according to claim 1, wherein a plurality of air ejection holes for air bubbling into the liquid in the side groove are formed at the bottom of the side groove.   The substrate polishing apparatus according to claim 8, wherein the air ejection holes are formed so as to be inclined obliquely upward toward the downstream side.

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